1. Field of the Invention
The invention relates to new lubricant additives effective as load carrying agents. More particularly, the load carrying agents are certain new organophosphorusbenzotriazole derivatives.
2. Discussion of the Prior Art
Benzotriazole is a well-known additive to lubricants, to power train fluids and to anti-freeze solutions. It is known, for example that benzotriazole can be utilized in a lubricating oil as a corrosion inhibitor. It can also be used as a copper deactivator in an anti-freeze solution (U.S. Pat. No. 3,597,353). Benzotriazole has been mixed with other materials such as phenol, an amine, a polyhydroxyquinone, an amine salt and an organic phosphite to produce an anti-oxidant for polyglycol based lubricants.
The use of phosphorus compounds, per se, as EP agents in lubricants is well known. The use of organic phosphorus compounds in combination with, for example, hindered phenols to produce load carrying additives for lubricants is known from U.S. Pat. No. 3,471,404. So far as is known, however, no art is available which suggests the reaction product of benzotriazole with an organophosphorus compound and its use as a load carrying agent.
Although benzotriazole does per se have such diversified activity in lubricant compositions, its solubility in such lubricant is extremely limited. There has accordingly been considerable work directed to overcoming the effect of this limited solubility without sacrificing its utility.